Fiber processing machines, such as cleaners, temporary storage devices, mixers or cards are used in the blow room for cleaning, mixing and separation of the fiber material into individual fibers as well as parallelization of the fibers.
In a blow room, the fibers to be processed for the spinning mill pass through a plurality of processing stages. In the first stage, the fibers are separated in the form of fiber flocks from fiber bales. So-called bale openers are mostly used for this purpose. These fiber flocks are removed from the bale opener by means of a pneumatic conveyor device and sent to a downstream cleaning machine. The pneumatic conveyor device consists essentially of a pipeline and a fan to create the required stream of conveyor air. The cleaned fiber flocks are in turn sent pneumatically from the cleaning machine to a mixer. The fiber flocks are then conveyed from the mixer by means of an additional transport section to a card, which separates the fiber flocks into individual fibers and then forms them into a fiber sliver.
The arrangement of individual machines in a blow room may be embodied in various ways, depending on the raw material to be processed and the product to be produced, among other things. For example, coarse cleaners and fine cleaners may be used, or temporary storage devices may also be used. A supplying machine in the sense of this patent application is a machine dispensing fiber material to a conveyor system. For transfer of the fiber material, the supplying machine comprises a supplying part. A machine to be supplied receives the fiber material. The machine to be supplied processes the received fiber material and, under some circumstances, can transfer it in turn to another conveyor system via a supplying part. Conveyance between machines is usually accomplished pneumatically in a stream of conveyor air generated by a fan. Simple machines, for example, metal separators, foreign material detection systems and foreign fiber detection systems or simple cleaners, which interrupt the conveyor line by their shape but do not suppress the actual conveyor stream, are integrated into the transport system and therefore also do not have any supplying part. The needs of the individual machines at the beginning, at the end and in the conveyor system must be met by the stream of conveyor air and/or a certain conveyor performance or production in order to have smooth functioning and also to meet the demand for a certain conveyor performance.
DE 31 51 697 A1 relates to the control of the charging of machines to be supplied for processing fiber material. The part of the machine to be supplied is regulated on the basis of the requirement of the machine to be supplied. The demand and thus production of the supplying machine are calculated on the basis of the filling level of the machine to be supplied. The machines set up between the supplying machine and the machine to be supplied are operated at the same speed. As a result of this regulation, downtimes of blow room machines are prevented. However, it is a disadvantage that even small amounts of fiber material are conveyed from the supplying machine to the machines to be supplied by means of machines in between. This does not take into account a minimum production which is necessary for a uniform quality in processing due to the speed set on the machine in between.
CH 670 257 A5 also teaches that the production level of a part to be supplied, belonging to a supplying machine, should be regulated by the demand of a machine to be supplied. Optimal operation of the machines in between is not taken into account in this process.
Stop-and-go operation is also known from the state of the art. In this type of operation, the supplying parts of the supplying machines are turned on and off on the basis of the demand of the machines to be supplied. This permits operation of the machine set up between the supplying machine and the machine to be supplied, each one at the same production level. However, the frequent start-up and stopping operations, which can lead to breakdowns due to unstable operating conditions or blockages within the individual machine, are a disadvantage.